Preparation and evaluation of killed NDV vaccine using new oil adjuvant

Preparation of inactivated oil Newcastle disease virus [NDV] vaccine using different new oil adjuvant Montonide ISA 70 VG, ISA 763A VG and ISA 775 as oil adjuvants in comparison with paraffin oil was carried out. The prepared vaccines with Montanide ISA 70 VG, 763 A VG and 775 VG induced high antibody titers than that induced by vaccines prepared with paraffin oil when determined by serological tests [HI and SNT]. The highest titer observed in prepared vaccine by ISA 70 VG oil adjuvant after 3 weeks post vaccination and remained high till 12 weeks post vaccination and has long duration of immunity reached to 12 month with a protective antibody titer and protection against challenge while prepared vaccine by Montonide ISA 763 A VG oil adjuvant reached 10 month with Montanide ISA 775 reached to 9 months, but in paraffin protective antibody titer reached only till 5 month

Expression of the bovine coronavirus spike glycoprotein subunits in insect cells using recombinant baculoviruses

In the present study, the bovine coronavirus [BCV] spike glycoprotein cleavage products [S1 and S2] were individually expressed in Spodoptera frugiperda [Sf9] insect cells, using a baculovirus expression system. The coding sequence of S1 and S2 gene fragments were amplified by RT-PCR and cloned into the baculovirus shuttle vector pBlueBac4.5/V5-His TOPO [R] TA. The cloned fragments were inserted into the genome of Autographa californica nuclear polyhydrosis virus [AcMNPV] under control of the polyhedrin promoter, through a process of homologous recombination between the shuttle vector and a linearized replication-defective baculovirus DNA [Bac-N-Blue[TM]]. Recombinant baculoviruses were selected by plaque purification; verified for the presence of target sequences using PCR and propagated for generation of high-titer viral stocks. Infection of insect cells with the recombinant baculoviruses revealed high-level expression of the target proteins as indicated by immunofluoresent test and solid phase ELISA using BCV-specific polyclonal antiserum

antigenic variation of foot and mouth disease virus of the last three isolates in Egypt

Three FMD viral isolates had been isolated from different outbreaks at three governorates [Sharquia, Suez, and Agga locality] during 1972, 1987, and 1993 from cattle respectively. The isolates were tested by coinplement fixation test [CFT] angainst the seven serotypes and the results revealed that all strains were of the type [O] FMD virus. The studied isolates were adapted after the 3[rd] and 4[th] passages to BEK cell cultures, they yielded infective titers ranging between 4 and 5.5 log 10 TCID[50] and complement fixing titers between 1.37-1.75 log[10] CFU/ml. Antigenic relationship and dominating state studies for the three isolates using the crosswise C.F.T. revealed that isolates [O[1]/72 and O[1] /87] and [O[1]/72] and O[1]/93] showing a little antigenic variation and can be classified as [Subtype similar but still different] and have a percentage between [32% to 70%] while isolates [O[1]/87 and O[1] /93] classified as [Subtype Similar] and have percentage between [70%-100%]. The dominance determination for isolated strains showed that isolate strain [O[1]/87] is dominating strain [O[1]/72 and O[1] /93] and strain O[1]/72 is dominating strain O[1]/93. The nucleotide sequence data of VPI of the isolated strains [O[1]/72, O[1]/87 and O[1]/93] revealed that the homology% FMD virus [O[1]/72, O[1] 87 with O[1]/93] were 86% and 88% respectively, while the homology% between O/87 and O/93 was 94%. This indicates a closer relationship between O[1]/87 and O[1]/93 isolates thorn to O[1]/72. The variation of the results between CF test and nucleotide sequence homology may be attnbuted to the fact that CF test is carried on the whole FMDV while the nucleotide sequence homology carried out on the level of VPI gene. However, this difference is not of a significant value that necessitates the change of the already applicable vaccinal strain

growth behaviour of the local isolate of lumpy skin disease virus [LSD]

The aim of this study was to identify and evaluate the kinetics and growth characteristics of LSDV in MDBK cell culture. The growth curve of the virus on MDBK cells denoted that the highest titer of cell associated virus was 4.48 TCID50/ml obtained 48 hours post- inoculation. The highest titer of cell free virus was 4.63 TCID50/ml 48 hours post-inoculation. LSDV is more cell associated than cell free. It is observed that virus growth and release was usually correlated with progression of CPE. The form and sequential cytopathic changes in MDBK cell culture were described

Isolation, Identification and sero conversion studies on BRSV in Egypt

In the present survey 250 nasal swabs and 400 sera samples were collected from calves, feed lot and diary cattle with different ages, seasons and different degree of respiratory signs, for BRSV isolation, identification and serodiagnosis. In addition to 150 calves apparently normal contact animals were examined. The collected samples represented six farms distributed throughout five Egyptian governorates. The obtained results proved that, 5 out 7 virus isolates were from calves 1-6 months old and another 2 isolates from unweaned calves 2-3 weeks old, 6 isolates were detected in spring season while, only one during winter season. Only 3 out of 7 titrated viral isolates were identified as BRSV by SNT and one more by direct FAT. The isolated strains were designated as RBSV Salhai 1994 and RBSV Alexandria 1994. The serodiagnosis results of 400 examined sera samples by SNT and ELISA revealed that 65 [16.25%] and 110 [27.5%] sera samples were positive, respectively. The antibodies titer ranged from 1/8 to 1/64. Maternal immunity through seroconversion study showed a fading of passive immunity completely at 5th month of age

Antimicrobial agents in Egyptian folk medicine

Aninvestigation was made into the presence of antimicrobia.l substances contained in certain Egyptian folk medicines. Seeds of cumin and caraway and leaves of guava, camphor, mint and tiliso and flowers of several herbaceous plants contained antimicrobial agents. These agents could be extracted from guava and camphor leaves by benzene, chloroform, ethyl ether and ethyl acetate and from cumin and caraway seeds by ethyl ether and alcohol and from the herbaceous flowers and mint leaves by benzene, ethyl ether and alcohol

presence of antimicrobial substances in certain green algae

The antimicrobial principles in three algae Chlorella vulgaris, Scenedesmus acutus and Colelastrurm probnscideum were extracted using a successive solvent system. The extracts were bioassayed against three different bacteria. The three algae contained different antimicrobial principles most of which were soluble in ethyl ether. The Gram negative Escherichia coli exhibited high tolerance to the antimicrobial principles compared to the Gram positive Staphylococcus aureus. No stimulating effects were recorded in the examined extracts